St George Partners with Boston Metal to Advance Next-Generation Niobium Processing at Araxá

About St George Mining Limited

St George Mining Limited (ASX: SGQ) is an Australian resources company advancing its 100 per cent owned Araxá niobium and rare earths project in Minas Gerais, Brazil. The project sits adjacent to CBMM’s world-leading niobium mining operations and has been described by the company as a de-risked, potentially world-class rare earths and niobium development opportunity. St George acquired Araxá in February 2025 and has since been progressing resource growth, metallurgical test work and broader pre-development study activity.

Strategic downstream alliance opens a new processing pathway

The latest announcement is significant because it extends St George’s focus beyond resource definition and into downstream processing potential. The company has signed a memorandum of understanding with Boston Electrometallurgical Corporation, known as Boston Metal, to trial Molten Oxide Electrolysis, or MOE, technology using material from Araxá. The aim is to assess whether MOE can be used in ferroniobium production and potentially support a new generation of niobium processing at the project.

That matters because processing is central to the economics and strategic value of niobium projects. St George said the trial has the potential to position the company as an industry leader in sustainable ferroniobium processing. Executive Chairman John Prineas said the technology offered an opportunity to develop cleaner and lower-cost production at Araxá, while Boston Metal Chief Executive Officer Tadeu Carneiro said the partnership could help create a sustainable and profitable pathway to production.

The alliance is not exclusive, and each party will bear its own workstream costs. Any longer-term use of the technology would require a separate formal agreement. St George also remains free to pursue other strategic investors and transactions involving Araxá. This keeps strategic flexibility intact while allowing the company to test a potentially differentiated processing route.

Boston Metal brings recognised technology and strong industry backing

A notable part of the announcement is the calibre of Boston Metal and the profile of its technology. St George described Boston Metal as a leader in innovative metals processing, with MOE originally developed at the Massachusetts Institute of Technology and commercialised by Boston Metal. The company said MOE is a platform technology that can enable efficient metals production from lower-grade raw materials and may offer higher yields, simpler process flow, lower cost and materially lower carbon emissions.

Boston Metal has also attracted strong financial and strategic backing. St George said the business has raised more than US$500 million from investors including BHP, BMW, Microsoft, ArcelorMittal, Vale and Aramco. The technology has also received major industry recognition, including the inaugural S&P Global Platts Metals Award for new technology in metals and mining, as well as inclusion by TIME Magazine among its Top 100 Influential Companies in 2024 and Best Inventions in 2025.

The quality of Boston Metal’s leadership is also relevant. St George noted that Boston Metal’s chairman and chief executive, Tadeu Carneiro, is a metallurgical engineer with extensive niobium experience, including almost 30 years at CBMM and a period as chief executive during which the global niobium market increased substantially. That adds technical credibility to the trial and suggests the work is being guided by people with deep sector expertise.

Potential processing advantages could be commercially meaningful

The traditional ferroniobium production route involves beneficiation by flotation, refining through hydrometallurgy and conversion through an aluminothermic process. St George said MOE has the potential to simplify beneficiation and eliminate the refining and conversion stages, which could materially reduce cost, waste and carbon emissions.

Another possible benefit is linked to Araxá’s broader rare earth profile. The company said slag produced from niobium processing is likely to contain a high concentration of rare earths, which may offer a further commercial advantage by reducing costs in the rare earth production flow. In practical terms, that means this alliance could have implications not only for niobium economics, but also for how St George eventually approaches integrated value extraction across the broader project.

Even so, St George is not relying solely on this pathway. The company said it is also carrying out metallurgical test work using traditional processing methods already proven in Araxá over more than 40 years. That dual-track approach appears designed to preserve optionality between an established technical model and an emerging lower-emissions alternative.

Araxá provides scale, location and development support

The broader investment case continues to be anchored in the quality and scale of the Araxá Project. St George acquired 100 per cent of the project on 27 February 2025. It is located in Minas Gerais, Brazil, adjacent to CBMM’s globally significant niobium operations, in a region with a long history of commercial niobium production, established infrastructure and a skilled workforce.

The company detailed the latest JORC 2012 Mineral Resource Estimate, which includes 70.91 million tonnes at 4.06 per cent TREO, 0.77 per cent MREO and 0.62 per cent Nb₂O₅ using a 2 per cent TREO cut-off. Within that, measured and indicated resources total 29.49 million tonnes at 4.56 per cent TREO and 0.75 per cent Nb₂O₅. An additional resource reported using a 0.2 per cent Nb₂O₅ cut-off adds 24.56 million tonnes at 0.52 per cent Nb₂O₅. St George said total Nb₂O₅ inventory associated with the Araxá Mineral Resource is 95.47Mt.

The company also highlighted government and institutional support. It has negotiated support for expedited approvals, signed a cooperation agreement with the State of Minas Gerais to help accelerate permitting, and has been selected for Brazil’s MagBras Initiative, which aims to establish an integrated and sustainable rare earth products supply chain within the country.

Outlook

Looking ahead, St George appears to be building Araxá on two fronts at once: expanding the project’s resource and development base while also testing a potentially more advanced downstream processing pathway. The Boston Metal alliance adds a strategic technology angle to an already large niobium and rare earth project and may support cleaner, lower-cost ferroniobium production if the trial proves successful. While the MoU does not yet lock in long-term commercial terms, it strengthens the project’s optionality and broadens the pathways available as St George continues drilling, metallurgical work and pre-development studies at Araxá.